Flying-boat hull



Feb. 19, 1929.

D. J. BRIMM, JR

FLYING BOAT HULL Filed Feb. 10, 1928 m m E V W.

DANIEL J. BRIMM JR.

STATES Pfilihl'l' OFFIQE.

DANIEL J. BRIMM, JR., OF WEST HEIETESTEAD, NEW YORK, ASSIGNOR TO IRELAND AIR- CRAFT INCORPORATED, A CORIPC'ZRATION OF NEW YORK.

FLYING-BOAT HULL.

Application filed February 10, 1928.

My invention relates to a system of float construction in wnich metal tubing, preterably steel, is employed; and an object of tee invention is to provide structural combinations and details of special value in the con struction of flying boat hulls, whereby a maximum of strength and rigidity is secured with a minimum of weight and material.

Heretot'ore, in the construction ot metal flying boat hulls or the like. it has been the practice to rivet the outer metal skin or sheet metal covering of the hull directly to the bull or skeleton tran'ie. Such hull tran'ie generally comprises a built-up skeleton in which the longitudinal, transverse and diagonal members thereof are constructed of sheet metal of various section-fiat metal stock being used in fabricating the various members of the frame.

Notwithstanding certain advantages resulting from the use of flat stock or sheet metal frame members, hull :trames thus constructed are extremely complicated and cannot under any circumstances be produced in quantity except at a prohibitive cost. The various frame members are not commercially procurable: each member must be formed or shaped up :t'rom a flat stock sheet or strip; at the various joints in the hull frame gussets or tillet pieces are necessary; and where a light metal such as aluminum or duralumin is used, riveted. rather than welded joints, are required to be made.

The present invention, as distinguished from the above, contemplates a lloat or hull skeleton in which all oi? the principal. longitudinal. transverse, and diagonal members of the :trame. are formed oi? commercially procurable tubular steel oil. closed hollow section throughout; in which all of said trame members are welded at their points o'l intersection: and in which the outer skin directly fastened to the hull lramo by suitable clips riveted or otherwise fastened to the skin and extending on the inside thereoit around the tubular frame members constituting the skeleton trame. An all metal hull thus constructed is stronger per unit of weight: lighter; infinitely less complicated: better adapted to quantity production: and very much cheaper than any acceptable metal float hereto'tore designed. As indicative at the desirability oi: using metal tubing of closed hollow section Serial No. 253,273.

throughout in aeroplane construction, it may be conservatively stated that practically all modern :tusclages, bodies, etc, other than floats, embody a similarly constructed skeleton frame. No one, however, in so far as I am aware, has found it either practical or expedient to use metal tubing substantially throughout in the design or construction of an aeroplane float or hull. The use, therefore, of metal tubing, in the fabrication of a hull or float Frame, is not only desirable but extremely advantageous for the reasons herein set forth.

Other and further advantages of the invention. such, for instance, as the method of attaching the outer skin or sheet metal covering to the skeleton frame, will be hereinafter ex plained.

In the drawings, wherein like reference characters denote like or corresponding parts,

Fig. 1 is a side elevation of the hull frame stripped oi" its outer covering;

Fig. is a plan View of the frame;

3 is an enlarged transverse vertical sectional vew on the lne 33 of Fig. 1, and

Figs. l. 5, (S. and 7, are fragmentary seetional views showing the manner in which the outer skin is attached.

In the embodiment of the invention selected for illi'istration. a flying boat hull of more or less conventional appearance is shown. It comprises a tore-body 10 and a tail extension 11. The underside of the tore-body 10 is of f-section throughout and terminates aft a vertical step 12. From the step 12 rearwardly. the hull bottom is preferably substantiall y flat and may or may not be provided with a second vertical step 13. That portion of the bottom surface ahead of the step 12 constitutes the hydroplaning bottom surtaco oi the hull.

The hull frame from how to stern, comprises tour principal longitudinal members or longerons. i. 0.. two upper and two lower. These principal longitudinal members are tormed of metal tubing ol? closed hollow section throughout. The upper two constitute the gunwale stringers and the lower two the chine stringers of the hull frame. The gunwale stringers, designated as 14, from a point of intersection at the bow, curve outwardly to a point substantially amidships, and thence approach. one another uniformly and gradused to hold the clips for the deflector strip in place. This means of attaching the cover sheets to the skeleton frame avoids the necessity of penetrating the principal frame members and at the same time holds the cover sheets firmly to the frame. If desired, reinforcing strips 35 may he provided on the outer surface of the side cover sheets to act as a binder extending lengthwise the hull frame.

A flying boat bull or other flotation body constructed as herein set forth may be pro duced in quantity at low cost: is strong; and light; and is eirpeciall v desirable by reason of the novel form of skin fastening means employed. Moreover, the outer skin. in its rela tion to the chine and gunwale strimrers. in each instance, lies tangent to that surface of the stringer againstwhich the adjacent edges of the cover sheets directly hear.

While I have described my invention in detail in its present i-referred emaauliment. it will be obvious to those skilled in th art after umilerstanding my invention. that various changes and modifications may he made therein without departing; from the spirit or scope thereof. I aim in the appended claims to cover all such modifications and changes.

\Vhat I claim is:

1. A hull for flying boats including a skele ton frame comprising chine and deck string;- ers formed of metal tubing of closed hollow section throughout, an outer sheet metal covoring for said frame, and means attached to the inner face of the sheet metal covering; for fastening it to the tubing of said frame.

A hull for flying boats including a skeleton frame comprising" chine stringers. deck stringers, and hull side vertical and diagronal members, said stringers and said members being formed of metal tubing of closed hollow sect-ion throughout, an outer sheet metal covering for said frame, and means at tached to the inner face of the sheet metal covering and beneath which said stringers and said members are carried for fastening: said covering to said frame.

3. A hull for flying heats including: a skeleton frame and a sheet metal cov ring, the skeleton frame cmnprising longitudinally e3ctending and transvcr.-=ely extending frame members of metal tubing of closed hollow section throughout, joints uniting the frame members at. tlwir points of intersection, and clips engaging the frame members and proriding bearing surfaces, at intervals of space, throughout the length and, depth of the skelcton frame for the attachment of said co\'er inc.

at. A hull for flying boats including a skeleton frame and a sheet metal covering, the skeleton frame comprising longitudinally extending and transversely extending; frame members of metal tubing of closed hollow section throughout, joints uniting the frame members at their points of intersection, and clips partially encircling the frame members and extending otl' therefrom at opposite sides thereof to provide at intervals of space throughout the length and depth of the skeleton frame a multiplicity of bearing surfaces against which said outer covering is fastened.

5. A hull for fly-inc boats including a skeleton frame and a sheet metal covering, the skeleton frame comprising longitudinally eX- tending' and transversely extending frame members of metal tubing of closed hollow section throughout, joints uniting the frame members at their points of intersection, ant clips fastened on the inside face of said outer covering and beneath which said frame members are carried to fasten said outer COVGIlIlg in place.

6. In a hull for flying boats, a skeleton frame of angular cross-section including a longitudinal stringer formed of metal tubing of closed hollow section throughout, a cover sheet bearing along one edge against one face of said stringer, a cover sheet hearing; along, one edge against a different face of said stringer, and a clip fastened to and extending from one to the other of said cover sheets on the inside of the skeleton frame, said clip for a portion of its length being in direct engagement with and fastened to said stringer.

7. In a hull for flying boats, a skeleton frame of angular cross-section including a chine stringer formed of metal tubingof closed hollow section throughout, a bottom cover sheet hearing along one edge. on the underside of said stringer, a side cover sheet bearing along one edge on the outer face of said stringer, and a clip fastened to and cxtending from one to the other of said cover sheets on the inside of the skeleton frame, said clip for a portion of its length being in direct engagement with and fastened to said chine stringer.

8. In a hull for flying boats, a skeleton frame of angular cross-section including a longitudinal stringer formed of metal tuhing of closed hollow section throughout, a cover sheet bearing along one edge against one face of said stringer, a cover sheet. hcaring along one edge against. a different face of said stringer, a. strip of angular cross-section extending lengthwise said stringer and beneath which the adjacent edges of said cover sheets are carried, and a. clip fastened to and extcmling' from one to the other of said cover sheets on the inside of the skeleton frame, said clip for a portion of its length, being in direct engagement with and fastened to said stringer.

9. In a hull for flyingboats, a skeleton frame of angular cross-section including a longitudinal stringer formed of metal tubing of closed hollow section throughout, a cover sheet fastened. along one edge thereof 'to one face of said stringer, a cover sheet and fastened to said coversheets on the inside of the skeleton frame, the clips, in each instance, being in direct engagement with and fastened to said stringer.

In testimony wher of I hereunte aflix my signature.

fastened along one edge thereof to a different face of said stringer, a sirip of an gular cross-section extending lengthwise said stringer and beneath which the adjacent edges of said cover sheets are carried, and

clips spaced longitudinally 01": said si'i'inger DANIEL J. BRIMM, JR. 

